Elastic-fluid turbine



Dec. 6, 1927. v 1,651,855 v G. B. WARREN ELASTIC mm) TURBINE F1]. :1June 24, 1924 TIPiI/Iill/ 7 v Fig.4.-

Ipvehtor: Flg- Glenn B.Wc1rre"n,

His Attorne Patented Dec, 6, 1927 I umrsn STAT/ES- PATENT owner...

.GLENN B. wannnn, or scfinnncrsnr;"nnw' onk, assrenon T GENERAL ELECTRIC1 I comramr, A. conrona'rron or NEW roan.

' ELASTIC-FLUID rename.

The present invention relates to elastic fluid turbines and especially.to diaphragm following stage, wheels 9 and 11 being carpackings for,turbines of-the type wherein the casing or housing is divided intostages. 6 by nozzle diaphragms, although-as tojcer-' tain broaderaspects, 1t is not necessarily In connection with the operation ofelastic fluid turbines,it is known that when a 0 turbine is operating atfull load, it runs more smoothly and .is less likely to vibratethan whenrunning at light load. This is because a turbine when runningat fullload is even- 1y heated and is 'subjectedto little temperature-andpressure changes; On the other, hand, when a turbine is running at lightload or, is being started-up, it may be subjected to changes intemperature and pressure of considerable magnitude and at such times ismuch 'more likely to operate unevenly or to vibrate.

Now, in the operation of'elastic fluid turdesirablefthat the packingsrun bines, it is with as close a clearance as it is possible to maintainso as to redpce the leakage to a minimum and it follows from theforegoing that because of the greater smoothness of operation, closerpacking clearance can be maintained when the turbine is operating a atfull load than when it is-being started up or is operating at lighterloads, and the o ject of my present invention is to provide an improvedpacking which is automatically adjusted so as to vary the clearance in.accordance with the load on the turbine, the clearance being the closestwhen the turbine is operating under full load conditions.

For 'a consideration of what I believe to be novel and my invention,attention is directed to the accompanying description and the claimsappended thereto.

In the drawing, Fig. I is a sectional view of a part of an elastic fluidturbine having a diaphragm packing embodying my invention; Figs. 2 and 3are detail views on a larger scale, illustrating the operation of myinvention; and Fig. 4 is a detail view ofia modification.

Referring to the drawing, 5 indicates the casing-of an elastic fluidturbine, which casing is divided into stages by nozzle diaphra s 6, thenozzles being indicated at 7. Nozz es 7 receive elastic fluid frombuckets 1 ja noaa mea manna. Serial No. 722,120.

charge it'to buckets 10 on a Wheel 11 in the ried by as'haft 12.' Onlyone diaphragm and they adjacent turbine wheels are shown in the drawing,the illustration of only a portion of a turbine being necessary to anunderstanding of my invention.

The construction so far described is a known one and i to be taken astypical of any turbine structure to which-my invention may be applied.

Now, according to my invention as carried out in connection withdiaphragm packing, I provide-on the shaft a packing element 13comprising annular packing teeth 14:" and on the diaphragm a packingelement 15 comprising annular packing teeth 16 which 00 operate withpacking teeth 14. When a tur-.

bine is in operation, there is a drop in pressureacross the diaphragmswhich drop in pressure increases with the load and this pressure on thediaphragm causes them to deflect somewhat toward the low pressure end ofthe machine, the deflections being the 8 on a-wheel 9 ofa precedingstage and disgreatest when the turbine isoperating at full load. 7 Incarrying out my invention, I take advantage of this fact and utilize thedeflection of the diaphra s due to increase in the load for varyin t eclearance of the packings. To this en I arrange the packings so thatwhen the diaphragm deflects toward the clearance in the packing will bedecreased and I then so construct the packing that there is ampleclearance at no load and so that the desired closer clearance will beestablished at full load due to the deflection of the diaphragm.

Referring to Figs. 1, 2 and'3, it will be seen that the desired resultis obtained by tapering the packing elements, the packing elements onboth the diaphragm and the ro tor being tapered or having conicalpacking surfaces in the present instance, and it will be clear thatWit-hthis arrangement when the diaphragm deflects toward the lowpressure end of the machine, 1'. e., toward the right in the drawing,the clearance in the packing will be decreased. I This is wellillustrated in the enlarged views in Figs. 2 and 3 wherein Fig. 2illustrates the normal no the low pressure end of the. turbine,

load position of the packing elements, and Fig. 3 illustrates theposition of the packing elements when the diaphragm is deflected underfull load conditions of operation. I 5. The specific type of packingelements comprising the straight teeth 14 cooperating with the slopingteeth 16 are shown only by way of example and as being a desirable formof packing structure to use in carrying out my invention. They form nopart of my present invention. Any suitable type of packing may be used.

In Figs. 1 to 3, the straight teeth are shown as being carried on therotor and the sloping teeth as being carried by the diaphragm. However,I may use the reverse of this arrangement and such a reverse arangementis shown in Fig. 4 of the drawing wherein 17 indicates the dia- 80phragm provided with the straight toothed packing element 18, and 19indicates the rotor or shaft provided with the sloping toothed packingelement 20. In this arrangement, the extent of the contact be-.

85 tween packing element 20 and shaft 19 is decreased by providing agroove 21 in the bore element 20. This serves to prevent rapid transferof heat from the packing element 20 to the shaft, a thing which, as .isknown, it is desirable to avoid. In accordance with the provisions of thpatent statutes, I have described the principle of operation of myinvention, together. with apparatus which I now consider to representthe best embodiments thereof, but I desire to have it understood thatthe ap-' paratus shown is only illustrative and that the invention maybe carried out by other means. a

What I claim as new and desire to secure by Letters Patent of the UnitedStates, 1s:

The combination with an axialflow multistage elastic fluid turbine, ofmeans for vary ing an interstage packing clearance therein in responseto load on the turbine, said means comprising a diaphragm between twostages, which diaphragm is sufliciently flexible to deflect toward thelow pressure end of the turbine increasingly as the pressure drop acrossit increases, a packing element carried by the diaphragm and arranged tomove therewith axially when the latter is deflected, and a packingelement with which said first-named packing element cooperates toprovide the inter-stage packing clearance, said packing elements beingannular in form, concentric, and tapered in the direction of the highpressure end of the turbine whereby the clearance between them is an 60nular and tapers in the same direction.

In witness whereof, I have hereunto set my hand this 23rd day of June1924.

y GLENN B. ARREN.

